GRE 777590, Instruction Manual

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8. Troubleshooting
8.1 Error code display on LED wire controller
Malfunction Error code Reason Solution
Inlet water temperature
sensor failure
PP1
The sensor in open or short
circuit
Check or change the sensor
Outlet water temperature
sensor failure
PP2
The sensor in open or short
circuit
Check or change the sensor
Heating condenser sensor
failure
PP3
The sensor in open or short
circuit
Check or change the sensor
Gas return sensor failure PP4
Connect some wire wrongly on
this point
Confirm there is nothing on this
point, restart the machine
Ambient temperature
sensor failure
PP5
The sensor in open or short
circuit
Check or change the sensor
Temperature difference
between water inlet and
outlet is too much
PP6
Water flow volume not
enough ,water pressure
difference is too low
Check the water flow volume or
water jammed or not
Cooling outlet water
temperature is too low
PP7
Water flow volume is not
enough
Check the water flow or water
system is jammed or not
First grade antifreeze
protection in Winter
PP7
Ambient temperature or water
inlet temperature is too low
Water pump will run
automatically for first grade
antifreeze
Second grade antifreeze
protection in Winter
PP7
Ambient temperature or water
inlet temperature is too low
Heat pump will start heating for
second grade antifreeze
Cooling condenser sensor
failure
PP8
Connect some wire wrongly on
gas return sensor position
Confirm there is nothing on this
point, restart the machine
High pressure protection EE1
1. Refrigerant is too much
2. Air flow is not enough
1. Discharge redundant
refrigerant from HP gas
system
2. Clean the air exchanger
Low pressure protection EE2
1. Refrigerant is not enough
2. Water flow is not enough
3. Filter jammed or capillary
jammed
1. Check if there is any gas
leakage ,re-fill the
refrigerant
2. Clean the air exchanger
3. Replace the filter or
capillary
Flow switch closed EE3 or "ON"
Low water flow, wrong flow
direction, or flow switch failure.
Check if the water flow is
enough and flow in right
direction, or else the flow
switch could be failed.
Power supply connections
wrong (for 3 phase unit)
EE4
Wrong connection or lack of
connection
Check the connection of power
cable
Inlet and outlet water
temperature difference
malfunction
EE5
Water flow volume is not
enough ,water pressure
difference is too low
Check the water flow rate ,or
water system is jammed or not
Communication failure EE8 Wire connection is not good Check the wire connection